Submersible pump-motor



Dec. 20, 1960 R. w. DOCHTERMAN Re- 24,909

suBMERsIBLE PUMP-MOTOR Original Filed Oct. 29, 1954 ,2 shams-sheet 1Dec. 20, 1960 R, W DOCHTERMAN I Re. 24,909

SUBMERSIBLE PUMP-MOTOR Original Filed Oct. 29, 1954 2 Sheets-Sheet 2United States Patent O SUBMERSIBLE PUMP-MOTOR Richard W. Dochterman,Fort Wayne, Ind., assignor to General Electric Company, a corporation ofNew York Original No. 2,782,720, `dated Feb. 26, 1957, Ser. No. 465,551,Get. 29, 1954. Application for reissue May 2, 1960, Ser. No. 26,389

15 Claims. (Cl. 103--'87) Matter enclosed in heavy brackets appears inthe original patent but forms no part of this reissue specilication;matter printed in italics indicates the additions made by reissue.

This invention relates to pump-motor assemblies, and more particularlyto those pump-motor assemblies which are adapted to be immersed in thefluid to be pumped.

There are a variety of pumping applications where Iit `is preferablefrom an economical point of view to build the pump and the motor as aunit. In such instances it will be apparent that it is generallynecessary to irnmerse the motor in the fluid to be pumped, which in manycases may be injurious to the motor parts because of corrosion,short-circuiting, etc. Many efforts have been made to solve the problemof protecting the motor from the uid in which it is immersed, most ofthe solutions being based on the idea of encasing the motor parts sothat they were entirely isolated from the fluid; while many of thesolutions have been relatively successful, it was, of course, alwaysnecessary to provide an eective seal between the motor and the pump sothat the fluid would not leak in through the relatively moving parts,thereby considerably increasing the cost of production. It will be seenthat it is desirable to eliminate the expense attendant upon theeffective insulation of the movable motor parts from the pump. It isproposed in the subject invention that this expense be eliminated bydeliberately leaving the movable parts of the motor open to the fluid,and enclosing only the stationary motor parts, which are generally themore sensitive insofar as corrosion and short-circuiting is concerned.Such a `structure permits a low cost pump-motor assembly which is simpleto manufacture and which, by the omission of any seal, removes thediiculties occasioned by lea-lts therein.

yIt is an object of this invention to provide a pumpmotor assembly whichwill incorporate the improved features set forth above.

Further objects and advantages of this invention will become apparentand the invention will be better understood by reference to thefollowing description and the accompanying drawings, and the features ofnovelty which characterize this invention will be pointed out withparticularity in the claims annexed to and forming a part of thisspecification.

This invention, in its broadest aspects, provides a pumpmotor assemblywherein a housing of insulating material has a bore formed therein. Astator member is entirely encased within the insulating material of thehousing and is so positioned that it surrounds the bore in relativelyclose proximity thereto. A rotor member is rotatably supported withinthe bore, and a pump impeller may be secured to the rotor so as to berotatable therewith. The

yentire assembly may be immersed in a fluid, generally a liquid, andwhen electric power is supplied to the stator member, the rotor memberwill be caused to rotate whereupon the pump impeller will pump the fluidas desired.

In the drawing, Figure 1 is 'a side view, partly broken away and partly"ice in cross section, of the improved pump-motor assembly of thisinvention;

Figure 2 is a View along lines 2--2 of Figure l;

Figure 3 is a View along lines 3 3 of Figure 1;

Figure 4 is an exploded vie-w in perspective, partly broken away andpartly in cross section, of the improved assembly of this invention; and

Figure 5 is a side view of the improved assembly in operation.

Referring now to the figures of the drawing, and in particular Figure 1,there is shown an improved pumpmotor assembly generally indicated by thenumeral 1. The assembly is substantially enclosed by a housing 2, whichis preferably formed of a stable insulating material having a low rateof fluid absorption. One such group of materials, for instance, includesthe epoxy resins which incorporate the features set forth above and, inaddition, provide a high degree of toughness for protective purposes.Housing 2 may be formed with a plurality of supporting members, such as3, on which it will stand when in operation.

Before the housing is formed, preferably by casting or molding, thestationary parts of the motor are assembled, as will be explained below.A stationary shaft 4 is tightly fitted, as by press-fitting, into thecentral opening 5 of a spider member 6 which has a plurality ofequispaced arms 7 extending radially outward. An annular member 8,preferably formed of some suitable metal, such as steel, is providedwith a circular inner flange 9 and a similar, but longer, concentricouter ange 10. The assembly of shaft 4 and spider member 6 is tightlyfitted within the inner flange 9 of member 8, and a dynamoelectricmachine stator member 11, conventionally rnade up of thin laminations 12of magnetic material, is tightly fitted into outer flange 10 of member8. [Stator member 11 is provided with a plurality of inwardly opening]The illustrated stator member 11 is of the salient pole type having apair of dametrically opposed pole pieces 13a which define a plurality ofwinding slots, such as 13, each of the slots preferably being providedwith a sheet of insulating material 14 covering its inner surface so asto separate laminations 12 from the stator coil 15 which is wound inslots 13.

It will be seen from Figure 2 that two coils 15 are provided. It will beunderstood, however, that the number of coils used is dependent onlyupon the particular type of dynamoelectric machines utilized, and thatthis number may be varied without any effect whatsoever as to theimproved structure constituting the invention.

It will be seen from the foregoing that the tight fitting of spider 6into inner ange 9 and of stator member 11 into concentric outer flange10 will provide a stator member which is maintained in exactconcentricity with stationary shaft 4. Member 8 is provided with aplurality of openings 16; a cable 17 containing a pair of conductorsl 18is passed through one of these openings to connection with the coils 15,the remainder of openings 16 being used for a purpose to be explainedherebelow. Housing 2 may then be formed, for instance, by placing theassembly of the stator member 11, spider 6, and shaft 4 within a moldand pouring in the housing material. The mold (not shown) willpreferably be of a shape to provide the outer conformation of thehousing 2 without further effort being necessary. The insulatingmaterial will flow through the openings 16 and will completely encasestator member 11 and coils 15. The mold is so formed as to leave anopening 19 within the housing, and an eyelet member 20 is tightly fittedover shaft 4, as shown, to determine the entrance of insulation materialto this cavity. Once the molding operation is complete, stator member 12will be completely encased in the housing 2 with a thin coat 21 ofinsulation covering the inner surface of the stator. In the case ofrelatively small motors, coating 21 is preferably on the order of .0linch at its narrowest part. This is suicient to insure protection of theinner surfaceof'the statorand is'small enough to avoid an unduly largeair gap when the\rotor (to-be described herebelow) is. assembled withinthe stator.

It is deemed preferable, where the housing Ais cast or molded, toprovide a mold of such a shape that cavity 19 wil-l be somewhat smallerthan shown in Figure l and then to attach a tool to stationary shaft 4and ream out cavity 19 to the desired size. This avoids the necessity ofachieving the thin coating 21 in the mold, since coating 21 may bemadeyrelatively thick and then teamed down to the desired size. The fact`that the tool (not shown) will be mounted von shaft 4 will insureperfect concentricity since, as explained above, shaft 4 is entirelyconcentric with'stator member 11.

Oncethe structure is completed to the extent set forth above, `a washermember 22'is secured againsteyelet member'20 and a bearing lmember 23 issecured over shaft 4,'in vrotatable relation thereto,-by the addition ofa second washer 24 and a second eyelet member 25' at end 26 of shaft 4.A rotor member 27, generally formed of thin laminations of magneticmaterial, such as 28, is secured to bearing 23 so as to be rotatabletherewith. Rotor 27 hasa plurality of slots (not shown) through whichpass bars 29 of non-magnetic conductive material. Bars 29 are shortedtogether at their ends by rings 30 and 31, thereby to form asquirrel-cage rotor. It will thus be seen that the electric motor usedin the illustration ofthe invention is a two-pole induction motor. Itwi11,-of course, be understood that other types of motors may besuccessfully used, and that this particular type has'been set forth incomplete detail for purposes of illustration. The outer surface of rotor27 is preferably coveredwith a thin coat 32 of insulation which may be,for example, either sprayed on, dipped, or brushed on. The assembly ofthe motor parts of the pump-motor unit is then complete. Rotor 27 isconcentrically mounted on shaft 4 within stator member 11 which isentirely encased within housing 2.

A11-additional feature which may be added, if desired, to further insurethe protection of stator member 11, is a knurled substantially tubularmember 33 which is placed about cable 17 before the casting process. Thematerial of housing 2 will adhere rmly to member 33 whichjin turn, has apinched-in section 34 to cause it to maintain cable 17 securelyin-place. This provision affords fa connectionwhich is-secured in placeand which yvwilln'ot provide lan opening for the fluid to be pumped to`enter within ythe housing to the detriment of the stator member 11.

lIt will be observed that end ring 31 of rotor 27 is exftendedaway fromthe rotor, as at 35, and a member 36 is` tightly fitted over extension35 so as to be rotatable 'with rotor 27. Member'36 has an outwardlyextending peripheral Vflange 37 with a plurality of openings 38 formedtherein. A circular piece 39 of sheet metal has a plurality of impellerblades 40 punched out of it. Impeller blades-40 vare each yformed with apair of tabs 41 "and 42 extending respectively from each side. Tab 41'ts within opening 38 in flange 37 to position the impeller plate -39with respect to member 36. Each tab 42 ts y-into an opening 43 formed inamember 44 to position :member 44 with respect to impeller member 39. Itwill be seen that by means of the'foregoing an impeller as- `sembly isformed consisting of the three parts 36, 39, and 44. -Member 44 ispreferably formed with a U-shaped 'cross section, that is, having anouter circular ilange 45 and an inner circular flange 46.

In forming impeller blades V40fout`of plate 39, a preferred method is touse la plate having the same original'diameter fas 'members 36 an'd`44;the impeller blades `40 are stamped 4out and Ibent over as shown, andthe remaining materialbetween the innen-'edge of the impeller bladesAand the original outer diameter of plate 39 is punched out and removed.

It will be seen from the foregoing that there has been provided acomplete impeller unit integrally secured to rotor 27 so as to berotatable therewith.

The bottom of housing 2 has a volute recess 47 formedy therein; recess47 forms the pump chamber, as is best. seen in Figures 3 and 4, andterminates in an access 48 which leads to a passageway l49, which ispreferably' formed in the-die mold during the casting of housing 2.. Apipe 50 is yplaced in connection with Vpassageway '49l so as to extendit all the Way from the volute pumping, chamber 47 at the bottom of thehousing out through topf of the housing. It will be seen in vFigure lthat pipe: 50 extends far enough above the top 51 of the housing: sothat a coupling may be effected with a pipe or hose,. 52.by any desiredmeans, such as clamp S3.

A plurality of relatively pliable strips of metal 55 are' cast intohousing 2, when it isformed, with their ends- 56 extending into thevolute chamber 47. Strips 55 extend respectively through openings 58 ina member S9.- Once parts 55 have respectively been fitted throughopenings 5S of member 59, their ends 56 may be bent over' so as tosecure member 59 to the remainder of the assembly. Member 59 is seatedon parts 60 and 61 formed in housing 2 surrounding volute chamber 47,and it will be seen in Figure 4 that member 59 is so shaped as tocorrespond substantially with the shape of the bottom of housing 2 so asto cover the bottom of the housing and substantially enclose the pumpingchamber 47. Member 59 has an opening 62 located in a protruding portion63 and formed by a re-entrant annular flange 69 thereof, as is bestobserved in Figure l. Portion 63 is also provided with a similar outerannular ange 68. When memer 59 is secured in place, opening 62 providesthe entranceway to the pumping chamber through impeller blades 40. Theprotrusion of part 63 provides closerunning surfaces between flanges 45and 46 and flanges 68 and 69 respectively to improve the pumpingefficiency.

When electric conductors 18 are connected to a source of power, rotor 27will be induced to turn and thereby cause the pump impeller assembly toturn with it. irnpeller blades `40 will d-raw in fluid through Vopening62 and force the Huid into pump chamber 47. The volute shape which hasbeen given to this chamber tends, as is well-known in the art, toconvert velocity into static pressure so that by the time the uid isforced around to access 48 and passageway 49 a relatively high amount ofpressure is available to force the fluid up the pipe. It will beobserved at this point that volute chamber 47 and the impeller assemblyare almost in contact at 64 (see Figure 3) so that practically all theuid pumped around in the chamber will tend to go through passageway 49and pipe 50 rather than through the small clearance 64 to be pumpedaround again.

Referring particularly to Figure 5, there is illustrated one possibleuse of the improved submersible pumpmotor assembly of this invention,wherein the assembly 1 is submerged in a liquid 65, such as water, forinstance, and is connected to a source of power through cable 17.Energization of coil'15 of stator member 11 through cable 17 Will causethe pump impeller assembly to rotate and force water through pipe 50 andhose 52 to be ejected as shown at 66. It'will be observed that no efforthas been made to prevent the uid, such as water, from passing entirelyaround the rotorandy inthe air gap, indicated at 67 in Figure l.Whatever the properties of the fluid, no harm can come to the stator member in view of the fact that it is completely encased within housing 2,even at the air gap where'it is ycovered by the thin coating 21. Thepart of rotor 27 most vulnerable to corrosion, that is, the outerperiphery, has also been coated as shown at 32 so that no matter whatfluid circulates Within the motor enclosure neither the stator nor therotor will be harmed thereby. Thus, the

assembly may be entirely -immersed in the uidto be more, this isachieved without any necessity for sealing the motor cavity from thepumping apparatus, and it is possible to make the assembly more compactand to avoid the expense of additional parts while achieving the desiredfunction in an efficient manner.

While exact structures have been set forth for illustrative purposes asto both the motor component and the pump component of the assembly, itwill be understood that the construction of either or both may be variedconsiderably from that shown while still incorporating the essentialfeatures of this invention. Therefore, while the invention has beenexplained by describing a particular embodiment thereof, it will beapparent that improvements and modifications may be made withoutdeparting from the scope of the invention as defined in the appendedclaims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. A motor comprising a housing of insulating material having a boreformed therein, said bore being formed to be open at one end of saidhousing and closed at the other end thereof, a stator member entirelyencased within said housing and positioned concentric with said bore andin relatively close proximately thereto, a shaft member secured withinsaid housing and positioned to extend into said bore concentrically withsaid stator member, means independent of said housing encased thereinand joining said stator member and said shaft member to ensureconcentricity thereof, an eyelet member rigidly positioned on said shaftmember, and a rotor member rotatably supported on said shaft andsubstantially axially aligned with said stator member, said eyeletmember being arranged to determine the axial position of said rotormember on said shaft member.

2. A motor comprising a stator member; a coil positioned on said statormember; an annular member having a circular outer flange, a circularinner ilange substantially -concentric with said outer ilange, and anelement connecting said flanges, said stator being tightly securedwithin said outer flange; a circular spider member having a centralopening arranged within said inner flange in tight engagement therewith;a shaft firmly secured within said central opening; an eyelet memberrigidly positioned on said shaft adjacent said spider member; a rotormember rotatably secured on said shaft and substantially axially alignedwith said stator member, said eyelet being arranged to determine theaxial position of said rotor member; said connecting element of saidannular member having an opening formed therein, an electric conductorarranged to pass through said opening and to be connected to said coils,sai-d conductor being adapted to be connected to a source of powerthereby to cause rotation of said rotor member; a housing composed ofinsulating nonabsorbent material arranged to encase completely saidstator member and said coil, said housing having a bore formed thereinso as to be lopen at one end thereof and closed at the other endthereof, said shaft being arranged to extend into said bore from saidclosed end thereby to position said rotor in said bore.

3. A motor comprising a housing of insulating material having a boreformed therein, said bore being formed to be open at one end of saidhousing and closed at the other end thereof, a stator member entirelyencased within said housing and positioned concentric with said bore andin relatively close proximity thereto, a shaft member secured withinsaid housing and positioned to extend into said bore concentrically withsaid stator member, means independent of said housing encased thereinjoining said stator members and said shaft to ensure concentricitythereof, and a rotor member rotatably supported on said shaft member andsubstantially axially aligned with said stator member.

4. A motor comprising a housing of insulating material having a boreformed therein, said bore being formed to be open at one end of saidhousing and closed at the other end thereof, a stator member entirelyencased within said housing and positioned concentric with said bore andin relatively close proximately thereto, a shaft member secured Withinsaid housing and positioned to extend into said bore concentrically withsaid stator member, metallic means encased in said housing joining saidstator member and said shaft to ensure concentricity thereof, and arotor member rotatably supported on said shaft member and substantiallyaxially aligned with said stator member.

5. A motor comprising a stator member, a coil positioned on said statormember; an annular member having a circular outer ilange, a circularinner flange substantially concentric with said outer flange, and anelement connecting said ilanges; said stator being tightly securedwithin said outer flange, a circular spider member having a centralopening arranged within said inner flange in tight engagement therewith,a shaft firmly secured within said central opening, a rotor memberrotatably secured on said shaft and substantially axially aligned withsaid stator member, said connecting element of said annular memberhaving an `opening formed therein, an electric conductor arranged topass through said opening and to be connected to said coil, saidconductor being adapted to be connected to a source of power thereby tocause rotation of said rotor member, and a housing composed ofinsulating non-absorbent material arranged to encase completely saidstator member and said coil, said housing having a bore formed thereinso to be open at one end of said housing and closed at the other endthereof, said shaft being arranged to extend into said bore from saidclosed end thereby to position said rotor in said bore.

6. A motor comprising a stator member, a coil positioned on said statormember; an annular member having a circular outer flange, a circularinner flange substantially concentric with said outer flange, and anelement connecting said flanges; said stator being tightly securedwithin said outer ilange, a circular spider member having a centralopening arranged within said inner flange in tight engagement therewith,a shaft firmly secured wtihin said central opening, a rotor memberrotatably secured on said shaft and substantially axially aligned withsaid stator member, said connecting element having an opening formedtherein, an electric conductor arranged to pass through said opening andto be connected to said coil, said conductor being adapted to beconnected to a source of power thereby to cause rotation of said rotormember; and a cast housing composed of an epoxy resin arranged toencase. completely said stator member, said coil, said annular member,said spider, and at least a portion of said electric conductor; saidhousing having a bore formed therein so as to be open at one end of saidhousing and closed at the other end thereof, said shaft being arrangedto extend into said bore from said closed end thereby to position saidrotor in said bore.

7. A pump-motor assembly comprising a housing of insulating materialhaving a bore formed therein, said bore being formed to be open at oneend of said housing and closed at the other end thereof, a stator memberentirely encased within said housing and positioned encircling said boreand in relatively close proximity thereto, a rotor member rotatablysupported within said bore, a pump impeller secured to Said rotor so as`to be rotatable therewith and being adapted to be immersed in a iluidand to pump the same when rotated, the end of said housing adjacent theopen end of said bore being formed into a volute recess, and means forcovering said recess thereby to form a pump chamber, said impeller beingpositioned substantially centrally in said recess thereby to pump fluidtherethrough, said housing so having a passageway formed therein as tocommunicate with said recess and adapted to receive the pumped fluid.

8. A pump-motor assembly comprising a housing of afgana insulatingmaterial having a bore formed therein, said bore beingforrued.tobeopenatone end of said housingand closed at the other end" thereof, astatormember entirely encased within saidrhousing and positioned encirclingsaid bore and in relatively close` proximity thereto, a rotor memberrotatably supported within said bore, a shaft arranged totextend-intosaid bore from said closed end, said rotor ,beingvrotatably mounted onsaid shaft thereby to position said rotor insaid bore, a` pump impellersecured to said rotor so as to be rotatable therewith, the end of said`housing adjacent the open end of said bore being formed into a voluterecess, a member arranged to be secured to said housing and to coversaid recess thereby to form a pumpchambensaid Vimpeller being positionedsubstantially centrally in lsaid recess, said member coveringV saidrecess having a substantially centrally located opening therein, saidhousing having a passageway formed therein so as to communicate withsaid recess wherebyupon rotation of said rotor member said impellerl isadapted to draw uid through said centrally located opening and pump theksame through said chamber into said passageway.

9. A pump-motor assembly comprising a housing of insulating materialhaving a bore formed therein, said bore being formed to be open at oneend of said housing and closedat the other end thereof, a stator memberentirely encased within said housing and positioned encircling said boreand in relatively close proximity thereto, a rotor member rotatablysupported within said bore, a pump impeller secured to said rotor so asto be rotatable therewith, a pump chamber formed at the end of saidhousing around said impeller, said housing having a passageway formedtherein in communication with the outlet part of said chamber, and aninlet passageway arranged in communication with said impeller wherebywhen said assembly is submerged in a uid and said rotor member is causedto rotate said impeller is adapted to draw iluid through said inlet andpump the same through said chamber into said formed passageway.

10. A pump-motor assembly comprising a housing of insulating materialhaving a bore formed therein,said bore being formed to be open at oneend of said housing and closed at the other end thereof, a stator memberentirely encased within said housing and positioned encircling said boreand in relatively close proximity thereto, a rotor member rotatablysupported within said bore, said rotor having an end ring formed vat theend thereof toward the open end of said bore, and a .pump impellerrotatably positioned in the open end of said bore, vsaid impellercomprising a plurality of impeller bladesand an annular member securedthereto, said annular Vmember having an inner circular ilange extendingaround and in tight-engagement with said end ring, said housingl havinga volute pump chamber formed at vthe openend of said bore about saidimpeller, a member arranged substantially to close said chamber, meansextending from said housing to secure said chamber-closing memberthereto, said chamber-closing member having an opening formed therein toprovide an inlet to saidimpeller, said 4housing having an outletpassageway formed therein in communication with the outlet portion ofsaid chamber whereby said impelleris adapted `to pump ,liquid` inthrough said inlet kand force the same lthrough said chamber and saidpassageway.

11. A pump-motor assembly comprising a housing` of insulating materialhaving a bore formedv therein, said bore being formed yto be open at oneendvof said `housing and closed at the other end thereof, a statormemberentirely encased within said housing andpositioned concentric with saidbore and in relatively close proximity thereto, a shaft member securedwithin said housing and positioned toextendinto said borevconcentrically .with sadi stator member, metallic means encased A,insaid heusing .joining said, stator member and Saidflshaft atuensureconcentricity thereof, a rotor member rotatably supported on said shaftmember and substantially axially aligned with said statormember, and apump impeller positioned in the open en d of said bore and secured vtosaid rotor so as to be rotatable therewith, said impeller being adaptedtobe immersed in a fluid and to pump the same when rotated, said housinghaving a pump chamber formed therein around said impeller,fsaid housingalso having formed therein a passageway in communication with theoutletpart of said chamber, and inlet means arranged in communicationwith said impeller whereby saidimpeller is adapted to drawuidbthroughsaid inlet means and pump the same through said chamber intosaid formed passageway upon rotation of said rotor member. 12. Apump-motor assembly comprising a stator member, a coil positioned onsaid stator member; annular member having a circular outer flange, acircular inner flange substantially concentric with said outer flange,and an element yconnecting said flanges; said stator being tightlysecured within said outer ange, a circular'spider member having acentral opening arranged within said inner ange in tight engagementtherewith, a shaft rmly secured within said central opening, a rotormember rotatably secured on said shaft and substantially axially alignedwith said stator member, said connecting element of said annular memberhaving an opening formed therein, an electric conductor arranged to passthrough said opening and to be connected to said coil, said` con--ductor being adapted to be connected to a source of power thereby tocause rotation of said rotor member,A a housing composed of aninsulating non-absorbent material arranged to encase completely saidstator member and said coil, said housing having a bore formed thereinto be openatoneend of said housing and closed at` the other end thereof,said shaft being arranged to extend into said borekfrom said closed endlthereby yto position said rotor in said bore, and a pump impellerpositioned in the open endV of said bore and secured to said rotor so asto be rotatable therewith, said impeller being adapted to be immersedlin a fluid and to pump the same when rotated, the end of said housingadjacent the openL end of said bore, being formed into a` volute recess,means for covering said recess thereby to form `aApump chamber, saidimpeller being positioned `substantially centrally Vin said recessthereby to pump fluid therethrough, said housing having a passagewayformed therein so Vas to communicate with saidrecess and adapted toreceive the pump fluid. v'

13. A pump-motor assembly comprising a stator mm ber, a coil positionedon said stator member; Van annular member having a circular outertlange, a circular inner flange substantially concentric with said outerange, and an element connecting said flanges; -said statormbeing tightlysecured within said outer ange, `a circular. spider member having acentral opening` arranged .withins'aid inner ange in tight engagementtherewith, a shaft firmly securedwithin said central opening, a rotormember rotatably ,secured on said shaft and ysubstantially axiallyaligned withsaid stator member, said connectingelement having an openingformed therein, an electric conductor vrarranged to pass through saidopening and to be connected to said coil,` said conductor4 being adaptedtop be connected to a source of power thereby to cause rotation ofv`said rotor member; a cast housing composed oflran epoxy resin arrangedto encase completely said stator member, said coil, ksaid annularmember, said spider,` and at least a portion of said electric conductor;said housing having a bore formed therein so as to be open at one end ofsaid housing and closed at the other end thereof, -said vshaft beingarranged toextendnto said rbore from-said closedend thereby to positionsaid rotor in saidfbore, said `rotorAhaving- Yan end ring formed at-fthe lend- `theret'if toward` the-openend, of said bore, and a pump`impeller positionedfinithe open-endet saidl bore, said yimpellersamprsinsra: plurality; ,of-i rt1pe11er-bladesA and a second annularmember secured thereto, said second annular 9 member having an innercircular ange extending around and in tight engagement with said endring, said housing having a volute pump chamber formed at the open endof said bore about said impeller, a member arranged substantially toclose said chamber, means extending from said housing to secure saidchamber-closing member thereto, said chamber-closing member having anopening formed therein to provide an inlet to said impeller, saidhousing having an outlet passageway formed therein in communication withthe outlet portion of said chamber whereby said impeller is adapted topump fluid in through said inlet and force the same through said chamberand said passageway.

14. In a pump-motor assembly, an electric motor comprising a housing ofinsulating material having a bore formed therein, said bore being formedto be open at one end of said housing and closed at the other endthereof, a stator member entirely encased within said housing andpositioned concentric with said bore and in relatively close proximitythereto, a shaft member secured within said housing and positioned toextend into said bore concentrically with said stator member, a spidermember secured about said shaft within said housing, an annular memberhaving an outer circular flange in tight engagement with the outersurface of said stator member and an inner circular flange substantiallyconcentric with said outer flange in tight engagement with the outersurface of said spider member thereby to ensure concentricity of saidstator member and said shaft member, and a rotor member rotatablysupported on said shaft member and substantially axially aligned withsaid stator member.

15. In a pumpmotor assembly, an electric motor comprising a statormember, a coil positioned on said stator member; an annular memberhaving a circular outer flange, a circular inner ange substantiallyconcentric with said outer ange, and an element connecting said flanges;said stator being tightly secured within said outer flange, a circularspider member having a central opening arranged within said inner angein tight engagement therewith, a shaft firmly secured within saidcentral opening, a rotor member rotatably secured on said shaft andsubstantially axially aligned with said stator member, said connectingelement having an opening formed therein, an electric conductor arrangedto pass through said opening and to be connected to a source of powerthereby to cause rotation of said rotor member, a housing composed of aninsulating non-absorbent material arranged to encase completely saidstator member and said coil, said housing having a bore formed thereinto be open at one end of said housing and closed at the other endthereof, said shaft being arranged to extend into said bore from saidclosed end thereby to position said rotor in said bore.

References Cited in the file of this patent or the origlnal patentUNITED STATES PATENTS 1,921,111 Apple Aug. 8, 1933 2,067,155 Levy et alJan. 5, 1937 2,286,993 Naul June 16, 1942 2,318,786 Korte May 11, 19432,548,133 Treat Apr. l0, 1951 2,649,048 Pezzillo Aug. 18, 1953 2,685,658Feiertag Aug. 3, 1954 2,695,969 Yates Nov. 30, 1954

